Title :
Novel predictive power control in a CDMA mobile radio system
Author :
Lau, F.C.M. ; Tam, W.M.
Author_Institution :
Dept. of Electron. & Inf. Eng., Hong Kong Polytech. Univ., Kowloon, Hong Kong
Abstract :
A novel prediction-based decisive power control algorithm has been proposed in the reverse link of a CDMA mobile radio system. An adaptive transversal filter, with the tap weights updated using the recursive least-squares (RLS) algorithm is constructed to predict the power gain in the next power measurement period. With two different measurement periods defined, the power gain in the next power control period is then predicted. Based on the predicted power gains, we signal-to-interference power ratio (SIR) estimation-based decision rules have been proposed to determine the power control commands for the mobiles. The novel algorithm has been observed to accomplish a lower outage probability when compared with the conventional power control algorithm with optimum power control threshold. Moreover, the effects of the number of measurement periods used for prediction, the mobile speeds, the prediction methods and the decision algorithms have been examined
Keywords :
Rayleigh channels; adaptive filters; adaptive signal processing; code division multiple access; filtering theory; land mobile radio; least squares approximations; multiuser channels; power control; power measurement; prediction theory; probability; radio links; radiofrequency interference; recursive estimation; telecommunication control; CDMA mobile radio system; RLS algorithm; SIR estimation-based decision rules; adaptive transversal filter; decision algorithms; mobile speeds; multipath Rayleigh fading channel; optimum power control threshold; outage probability; power control algorithm; power control commands; power gain prediction; power measurement period; prediction methods; predictive power control; recursive least-squares algorithm; reverse link; signal-to-interference power ratio; tap weights; Adaptive systems; Gain measurement; Land mobile radio; Multiaccess communication; Power control; Power measurement; Prediction methods; Resonance light scattering; Transversal filters; Velocity measurement;
Conference_Titel :
Vehicular Technology Conference Proceedings, 2000. VTC 2000-Spring Tokyo. 2000 IEEE 51st
Conference_Location :
Tokyo
Print_ISBN :
0-7803-5718-3
DOI :
10.1109/VETECS.2000.851612